Automatic breadmakers for home use are becoming increasingly popular, in part because the user is able to prepare specialty and custom loaves of bread of a type not available or not readily available at commercial outlets. Another reason for the popularity of such breadmakers is that bread can be consumed when warm, i.e., immediately at the conclusion of baking. Warm, freshly baked bread has a unique aroma and texture that adds to dining pleasure.
There are a number of examples of automatic breadmakers in the patent literature. U.S. Pat. Nos. 5,415,081 (Yoshida et al.); 4,415,799 (Tanaka); 4,951,559 (Arao et al.); 4,538,509 (Ojima et al.) and 4,984,512 (Takahashi et al.) are but a few.
A significant problem in breadmakers of the prior art involves regulation of the time period during which the dough is permitted to rise. This "dough rise period" is the time period during which carbon dioxide gas emitted from yeast in the dough causes the dough to rise or expand.
Typically there are several dough rise periods involved in preparation of dough with an automatic breadmaking machine. The dough ingredients (e.g., wheat flour, sugar, water, milk, yeast, shortening, salt, etc.) are first combined and then mixed by the breadmaking machine. The dough is then permitted to rise. Following this first rise period, the machine kneads and "degasses" the dough, causing carbon dioxide to be released from the dough and reducing the size of the dough mass. The dough is then permitted to rise a second time. A further step of kneading/degassing is typically followed by a third, or final, dough rise period.
Proper regulation of the final dough rise period is particularly important to ensure that the dough has the proper size, appearance, and texture prior to baking. If the final dough rise period is of insufficient duration, the dough mass will be short and flat. The appearance of the final baked product will be stunted and, at least in appearance, unlike that of a commercial bakery loaf. Moreover, inadequate carbon dioxide in the dough will cause the texture of the dough to be unsatisfactory. Such dough will be dense, chewy, tough and generally unappealing.
The duration of the dough rise period needed may vary based on conditions such as the type of dough being used. For example, it is well known that whole wheat dough takes longer to rise than dough made with sifted flour. Temperature and humidity affect the rate at which dough rises.
The rise time may also be affected by the biological activity of the yeast or the amount of yeast used. All of these concerns suggest that the ability to regulate or extend the final dough rise period would be of great assistance in preparation of bread with an automatic breadmaker. Prior art automatic breadmakers do not address these problems in an entirely satisfactory way.
Many known automatic breadmakers have a final dough rise period but with a preset duration that cannot be changed. Importantly, these breadmakers do not provide for extension of the final dough rise period in the event the dough has failed to rise as expected. For example, the disclosures of the Tanaka and Arao et al. patents involve final dough rise periods, the durations of which are preset and cannot be extended.
The Ojima et al. patent describes three dough rise, or "fermentation," periods each of a preprogrammed duration. Again, there is no accommodation for extending the final dough rise period in the event the dough has not risen a sufficient amount.
The Yoshida et al. patent describes a mechanism to extend the final dough rise period but this arrangement is less than satisfactory because selection of the extended dough rise period may only be made after the machine operating cycle is initiated and before (but not after) the final rise period begins. This is particularly inconvenient if, during the final dough rise period, the user discovers that the dough has failed to rise as anticipated.
And another inconvenience is that the user of the breadmaker is unable to use (at least unable to conveniently use) any delayed-start feature to start the machine at, e.g., 2:00 AM so that fresh bread available early in the morning. In other words, the user must be present at machine startup if the final rise period is to be extended.
The Takahashi et al. patent describes three modes of operation for a breadmaker, namely, fully automatic, semi-automatic and manual. In the manual mode it is possible for the user to manually shorten the preprogrammed duration of each step of the breadmaking process. The duration of each step may be stored in memory for subsequent use.
Takahashi's manual mode, the only mode in which the duration of the final rise period may be changed, is complicated and requires the user to select the duration of all time increments of the overall breadmaking cycle. If such time increments are not so selected, the machine uses "default" durations programmed into it. And one may not increase the preprogrammed "default" duration of the final rise period but may only decrease such duration. To put it in other words, no way is provided to extend the default time, should the dough not rise as anticipated.
Thus, known automatic breadmakers are incapable of providing the user with the ability to conveniently and easily regulate the duration of the final rise period both before breadmaker activation and during the final dough rise period itself. An improved method of operation for a breadmaker permitting greater flexibility in regulation of the final dough rise period so as to provide attractive, soft and delicious bread would be an important advance in the art.